add drone test pipeline

.drone.yml

@@ -0,0 +1,17 @@
+kind: pipeline
+type: docker
+name: secret-test
+
+steps:
+  - name: show-env
+    image: alpine:3.19
+    environment:
+      TEST_VAR: HelloWorld
+      SECRET_VAR:
+        from_secret: test_secret
+    commands:
+      - echo "==== ENVIRONMENT TEST ===="
+      - echo "Normal var: $TEST_VAR"
+      - echo "Secret var: $SECRET_VAR"
+      - echo "All envs (filtered):"
+      - env | grep -E "TEST_|SECRET_|DRONE_"